Modules/Storage/ATA/mbr.c

   1 /*
   2  * Acess2 IDE Harddisk Driver
   3  * - MBR Parsing Code
   4  * mbr.c
   5  */
   6 #define DEBUG   0
   7 #include <acess.h>
   8 #include "common.h"
   9
  10 // === PROTOTYPES ===
  11 void    ATA_ParseMBR(int Disk, tMBR *MBR);
  12 Uint64  ATA_MBR_int_ReadExt(int Disk, Uint64 Addr, Uint64 *Base, Uint64 *Length);
  13
  14 // === GLOBALS ===
  15
  16 // === CODE ===
  17 /**
  18  * \fn void ATA_ParseMBR(int Disk, tMBR *MBR)
  19  */
  20 void ATA_ParseMBR(int Disk, tMBR *MBR)
  21 {
  22          int    i, j = 0, k = 4;
  23         Uint64  extendedLBA;
  24         Uint64  base, len;
  25
  26         ENTER("iDisk", Disk);
  27
  28         // Count Partitions
  29         gATA_Disks[Disk].NumPartitions = 0;
  30         extendedLBA = 0;
  31         for( i = 0; i < 4; i ++ )
  32         {
  33                 if( MBR->Parts[i].SystemID == 0 )       continue;
  34                 if(     MBR->Parts[i].Boot == 0x0 || MBR->Parts[i].Boot == 0x80 // LBA 28
  35                 ||      MBR->Parts[i].Boot == 0x1 || MBR->Parts[i].Boot == 0x81 // LBA 48
  36                         )
  37                 {
  38                         if( MBR->Parts[i].SystemID == 0xF || MBR->Parts[i].SystemID == 5 ) {
  39                                 LOG("Extended Partition at 0x%llx", MBR->Parts[i].LBAStart);
  40                                 if(extendedLBA != 0) {
  41                                         Warning("Disk %i has multiple extended partitions, ignoring rest", Disk);
  42                                         continue;
  43                                 }
  44                                 extendedLBA = MBR->Parts[i].LBAStart;
  45                                 continue;
  46                         }
  47                         LOG("Primary Partition at 0x%llx", MBR->Parts[i].LBAStart);
  48
  49                         gATA_Disks[Disk].NumPartitions ++;
  50                         continue;
  51                 }
  52                 // Invalid Partition, so don't count it
  53         }
  54         while(extendedLBA != 0)
  55         {
  56                 extendedLBA = ATA_MBR_int_ReadExt(Disk, extendedLBA, &base, &len);
  57                 if( extendedLBA == -1 ) break;
  58                 gATA_Disks[Disk].NumPartitions ++;
  59         }
  60         LOG("gATA_Disks[Disk].NumPartitions = %i", gATA_Disks[Disk].NumPartitions);
  61
  62         // Create patition array
  63         gATA_Disks[Disk].Partitions = malloc( gATA_Disks[Disk].NumPartitions * sizeof(tATA_Partition) );
  64
  65         // --- Fill Partition Info ---
  66         extendedLBA = 0;
  67         for( j = 0, i = 0; i < 4; i ++ )
  68         {
  69                 LOG("MBR->Parts[%i].SystemID = 0x%02x", i, MBR->Parts[i].SystemID);
  70                 if( MBR->Parts[i].SystemID == 0 )       continue;
  71                 if( MBR->Parts[i].Boot == 0x0 || MBR->Parts[i].Boot == 0x80 )   // LBA 28
  72                 {
  73                         base = MBR->Parts[i].LBAStart;
  74                         len = MBR->Parts[i].LBALength;
  75                 }
  76                 else if( MBR->Parts[i].Boot == 0x1 || MBR->Parts[i].Boot == 0x81 )      // LBA 58
  77                 {
  78                         base = (MBR->Parts[i].StartHi << 16) | MBR->Parts[i].LBAStart;
  79                         len = (MBR->Parts[i].LengthHi << 16) | MBR->Parts[i].LBALength;
  80                 }
  81                 else
  82                         continue;
  83
  84                 if( MBR->Parts[i].SystemID == 0xF || MBR->Parts[i].SystemID == 5 ) {
  85                         if(extendedLBA != 0) {
  86                                 Log_Warning("ATA", "Disk %i has multiple extended partitions, ignoring rest", Disk);
  87                                 continue;
  88                         }
  89                         extendedLBA = base;
  90                         continue;
  91                 }
  92                 // Create Partition
  93                 ATA_int_MakePartition(
  94                         &gATA_Disks[Disk].Partitions[j], Disk, j,
  95                         base, len
  96                         );
  97                 j ++;
  98
  99         }
 100         // Scan extended partitions
 101         while(extendedLBA != 0)
 102         {
 103                 extendedLBA = ATA_MBR_int_ReadExt(Disk, extendedLBA, &base, &len);
 104                 if(extendedLBA == -1)   break;
 105                 ATA_int_MakePartition(
 106                         &gATA_Disks[Disk].Partitions[j], Disk, k, base, len
 107                         );
 108         }
 109
 110         LEAVE('-');
 111 }
 112
 113 /**
 114  * \brief Reads an extended partition
 115  * \return LBA of next Extended, -1 on error, 0 for last
 116  */
 117 Uint64 ATA_MBR_int_ReadExt(int Disk, Uint64 Addr, Uint64 *Base, Uint64 *Length)
 118 {
 119         Uint64  link = 0;
 120          int    bFoundPart = 0;;
 121          int    i;
 122         tMBR    mbr;
 123         Uint64  base, len;
 124
 125         if( ATA_ReadDMA( Disk, Addr, 1, &mbr ) != 0 )
 126                 return -1;      // Stop on Errors
 127
 128         for( i = 0; i < 4; i ++ )
 129         {
 130                 if( mbr.Parts[i].SystemID == 0 )        continue;
 131
 132                 // LBA 24
 133                 if( mbr.Parts[i].Boot == 0x0 || mbr.Parts[i].Boot == 0x80 ) {
 134                         base = mbr.Parts[i].LBAStart;
 135                         len = mbr.Parts[i].LBALength;
 136                 }
 137                 // LBA 48
 138                 else if( mbr.Parts[i].Boot == 0x1 || mbr.Parts[i].Boot == 0x81 ) {
 139                         base = (mbr.Parts[i].StartHi << 16) | mbr.Parts[i].LBAStart;
 140                         len = (mbr.Parts[i].LengthHi << 16) | mbr.Parts[i].LBALength;
 141                 }
 142                 else {
 143                         Log_Warning("ATA MBR",
 144                                 "Unknown partition type 0x%x, Disk %i Ext 0x%llx Part %i",
 145                                 mbr.Parts[i].Boot, Disk, Addr, i
 146                                 );
 147                         return -1;
 148                 }
 149
 150                 switch(mbr.Parts[i].SystemID)
 151                 {
 152                 case 0xF:
 153                 case 0x5:
 154                         if(link != 0) {
 155                                 Log_Warning("ATA MBR",
 156                                         "Disk %i has two forward links in the extended partition",
 157                                         Disk
 158                                         );
 159                                 return -1;
 160                         }
 161                         link = base;
 162                         break;
 163                 default:
 164                         if(bFoundPart) {
 165                                 Warning("ATA MBR",
 166                                         "Disk %i has more than one partition in the extended partition at 0x%llx",
 167                                         Disk, Addr
 168                                         );
 169                                 return -1;
 170                         }
 171                         bFoundPart = 1;
 172                         *Base = base;
 173                         *Length = len;
 174                         break;
 175                 }
 176         }
 177
 178         if(!bFoundPart) {
 179                 Log_Warning("ATA MBR",
 180                         "No partition in extended partiton, Disk %i 0x%llx",
 181                         Disk, Addr);
 182                 return -1;
 183         }
 184
 185         return link;
 186 }